title: Glycoproteins gE and gI are required for efficient KIF1A-dependent anterograde axonal transport of alphaherpesvirus particles in neurons.
abstract: Alphaherpesviruses, including pseudorabies virus (PRV), spread directionally within the nervous systems of their mammalian hosts. Three viral membrane proteins are required for efficient anterograde-directed spread of infection in neurons, including Us9 and a heterodimer composed of the glycoproteins gE and gI. We previously demonstrated that the kinesin-3 motor KIF1A mediates anterograde-directed transport of viral particles in axons of cultured peripheral nervous system (PNS) neurons. The PRV Us9 protein copurifies with KIF1A, recruiting the motor to transport vesicles, but at least one unidentified additional viral protein is necessary for this interaction. Here we show that gE/gI are required for efficient anterograde transport of viral particles in axons by mediating the interaction between Us9 and KIF1A. In the absence of gE/gI, viral particles containing green fluorescent protein (GFP)-tagged Us9 are assembled in the cell body but are not sorted efficiently into axons. Importantly, we found that gE/gI are necessary for efficient copurification of KIF1A with Us9, especially at early times after infection. We also constructed a PRV recombinant that expresses a functional gE-GFP fusion protein and used affinity purification coupled with mass spectrometry to identify gE-interacting proteins. Several viral and host proteins were found to associate with gE-GFP. Importantly, both gI and Us9, but not KIF1A, copurified with gE-GFP. We propose that gE/gI are required for efficient KIF1A-mediated anterograde transport of viral particles because they indirectly facilitate or stabilize the interaction between Us9 and KIF1A.
authors.affiliation: Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA.
authors.forename: Radomir
authors.initials: R
authors.lastname: Kratchmarov
authors.forename: Tal
authors.initials: T
authors.lastname: Kramer
authors.forename: Todd M
authors.initials: TM
authors.lastname: Greco
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Taylor
authors.forename: Toh Hean
authors.initials: TH
authors.lastname: Ch'ng
authors.forename: Ileana M
authors.initials: IM
authors.lastname: Cristea
authors.forename: Lynn W
authors.initials: LW
authors.lastname: Enquist
mesh_terms: D018138:Alphaherpesvirinae / Q000235:genetics / Q000472:pathogenicity / Q000502:physiology*; D000818:Animals; D001370:Axonal Transport / Q000502:physiology; D002460:Cell Line; D002478:Cells, Cultured; D011558:Herpesvirus 1, Suid / Q000235:genetics / Q000472:pathogenicity / Q000502:physiology*; D054884:Host-Pathogen Interactions; D047908:Intracellular Signaling Peptides and Proteins; D016547:Kinesins / Q000502:physiology*; D008074:Lipoproteins / Q000235:genetics / Q000502:physiology*; D009474:Neurons / Q000502:physiology* / Q000821:virology*; D016716:PC12 Cells; D010750:Phosphoproteins / Q000235:genetics / Q000502:physiology*; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000502:physiology; D013552:Swine; D014759:Viral Envelope Proteins / Q000235:genetics / Q000502:physiology*; D014764:Viral Proteins / Q000235:genetics / Q000502:physiology*; D014771:Virion / Q000502:physiology
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; C490575:Kif1a protein, rat; D008074:Lipoproteins; D010750:Phosphoproteins; D011993:Recombinant Fusion Proteins; C491630:US9 protein, Suid herpesvirus 1; D014759:Viral Envelope Proteins; D014764:Viral Proteins; C089580:glycoprotein E, Suid herpesvirus 1; C042966:pseudorabies virus glycoproteins; D016547:Kinesins